Formula One explained: Pirelli tyres

At each grand prix weekend in 2011 The National will look at a different aspect of Formula One and how it works. This week Gary Meenaghan looks at tyres.

• Pirelli's relationship with Formula One came to an end in Australia 20 years ago and it is here where it resumes again this weekend.

• The Italian tyre supplier was asked to provide six variations, for different weather and track conditions, to the 12 F1 teams competing in this year's championship and that is exactly what they have done.

• Each grand prix will see four tyres available: wet, intermediate, prime and option. However, the prime and option tyres will be selected before each race from a range of compounds: hard, medium, soft and super-soft.

• Each tyre will be recognisable by a different colour of branding on the rubber and will degrade at different rates.

• Pirelli has indicated it wants at least one step between the choices for prime and option. Therefore, for example, teams will not be able to run soft and super soft at the same race.

• For this weekend's season opener in Australia, the Italian company has opted for hard as the prime tyre and soft as the option.

• Last season, drivers were allocated 14 sets of dry-weather tyres each weekend, but that has been reduced to 11 for this year.

• Drivers will be provided with three sets (two prime, one option) to use in Friday's two practice sessions, but must return one set after each session. A further eight sets will be allocated for Saturday and Sunday, but one set of each compound must be handed back before qualifying begins.

• If a driver fails to use both prime and option tyres during a dry race, they will be excluded from the results.

• Pirelli also has the option to give teams an additional set of tyres for use during Friday practice, but only for evaluation purposes. They chose to use this option in Australia yesterday.